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In the development of high‐performance organic solar cells (OSCs), the self‐organization of organic semiconductors plays a crucial role. This study focuses on the precisely manipulation of molecular assemble via tuning alkyl side‐chain topology in a series of low‐cost nonfused‐ring electron acceptors (NFREAs). Among the three NFREAs investigated, DPA‐4, which possesses an asymmetric alkyl side‐chain length, exhibits a tight packing in the crystal and high crystallinity in the film, contributing to improved electron mobility and favorable film morphology for DPA‐4. As a result, the OSC device based on DPA‐4 achieves an excellent power conversion efficiency of 16.67 %, ranking among the highest efficiencies for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) have attracted extensive attention from both academia and industry in recent years due to their remarkable improvement in power conversion efficiency (PCE). However, the Golden Triangle (the balance of efficiency‐stability‐cost) required for large‐scale industrialization of OSCs still remains a great challenge. Here, a new nonfused‐ring electron acceptor (NFREA) BF and its polymerized counterpart PBF were designed and synthesized, and their photovoltaic performance, storage stability and material cost were systematically investigated. When blended with a widely‐used polymer donor PBDB‐T, the PBF‐based all‐polymer solar cell (all‐PSC) displayed a record high PCE of 12.61% for polymerized NFREAs (PNFREAs) with an excellent stability (95.2% of initial PCE after 800 h storage), superior to the BF counterpart. Impressively, PBF‐based all‐PSC possesses the highest industrial figure‐of‐merit (i‐FOM) value of 0.309 based on an efficiency‐stability‐cost evaluation, in comparison to several representative OSC systems (such as PM6:Y6 and PBDB‐T:PZ1). This work provides an insight into the balance of efficiency, stability, and cost, and also indicates that the PNFREAs are promising materials toward the commercial application of OSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing thiazole and 4‐chlorothiazole as the A′ units, two A‐D‐A′‐D‐A type nonfused‐ring electron acceptors (NFREAs) Tz‐H and Tz‐Cl were designed and synthesized. Replacing thiazole in Tz‐H with 4‐chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz‐Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz‐H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing thiazole and 4‐chlorothiazole as the A′ units, two A‐D‐A′‐D‐A type nonfused‐ring electron acceptors (NFREAs) Tz‐H and Tz‐Cl were designed and synthesized. Replacing thiazole in Tz‐H with 4‐chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz‐Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz‐H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

Many breakthroughs on security and privacy-preserving techniques have emerged to mitigate the trust loss of cloud hosting environment caused by various types of attacks. To enhance memory-level security of multi-keyword fuzzy search, a widely occurred query request, we take the initiative to apply Trusted Execution Environment (a.k.a TEE) technology to our protocol design which provides hardware-based tamper-proof enclaves. Then we propose the Edit Distance-based Obfuscation Mechanism to further protect the query process executed outside TEE against access pattern leakage. With concerns of practicality and performance, we also propose the two-layer fuzzy index structure and Trend-aware Cache. The former addresses the space limitation of TEE memory for searching large datasets, while the latter optimizes the cache utility of TEE with trend-aware coordinator to effectively reduce the communication overhead. [ABSTRACT FROM AUTHOR]